"IOException while reading user_dictionary: /app/config/userdict_ko.txt"

I'm using elastic cloud deployment and i want to add user dictionary to deployment

so I add custom plugin with .zip file which is consist of /dictionaries/userdict_ko.txt

and I manage plugins and settings. but when i create index like following

"settings": {
		"index": {
        "analysis": {
            "tokenizer": {
              "nori_user_dict":{
                "type": "nori_tokenizer",
                "user_dictionary": "userdict_ko.txt"
              }
            },
            "analyzer":{
              "nori_korean":{ 
                 "type":"custom",
                 "tokenizer":"nori_tokenizer"
              },
              "custom_smartcn":{
                "type":"custom",
                "tokenizer":"smartcn_tokenizer"
              }
            }
        }
    }
	},

i show error

{
  "error" : {
"root_cause" : [
  {
    "type" : "illegal_argument_exception",
    "reason" : "IOException while reading user_dictionary: /app/config/userdict_ko.txt"
  }
],
"type" : "illegal_argument_exception",
"reason" : "IOException while reading user_dictionary: /app/config/userdict_ko.txt",
"caused_by" : {
  "type" : "no_such_file_exception",
  "reason" : "/app/config/userdict_ko.txt"
}
  },
  "status" : 400
}

what did i do wrong??? how can i add my custom dictionary to elastic cloud deploment
and how can i access filesystem??